PROTOZOA RHIZOPODA. 



153 



these are assimilated by the sponge particles in a similar 



JL 



FIG. 62. SPONGILLA. 



A 1, 1 ', spicula ; 2, 2 /, gemmules ; 3, ciliated embryo. B, section of spon/jilla 

 the arrows indicate the direction of the currents; a, outer layer; b, inner layer; 

 c, ciliated chamber; <?, exhalant orifice. C, Mass of sponyilla the arrows in- 

 dicate the inhalant apertures; c c, openings leading to ciliated chambers; 

 single exhalant aperture hi the centre. 



